Valved pump piston assembly



- "5115.23, 1946. o. A. KEHLE I 0 2 VALVED PUMP PISTON ASSEMBLY Filed March 6, 1945 V Patented July 23,- 1946 V VALVED PUMP PISTON ASSEMBLY Ottmaro A.. Kehle; .Van Nuy s,v,Calif., assignor to Adel Precisi n Produc m a. corporation of California Applicat on-March 6, mas

-7 clai (01. i

This invention relates topumps of the manually operable type as used in the hydraulic; systems of aircraft, and more particularly pertains to a valved piston assembly ior such pumps and forlsuch other uses and applications to which saidassembly is suited. 7

One of the objects of this invention is to provide a. valved piston assembly in which the piston rod, piston proper or piston head and certain novel check valve parts are constructed, combined and inter-related in such manner as to greatly reduce the amount of machiningoperations, the produc tion costs, the amount of material employed, the servicing and upkeep costs and the number of parts compared to valved piston units as heretofore made. v to e Another object of this invention is to provide a valved piston unit such-as described which may be quickly and easily assembled and disassembled.

a further object is to provide a valve piston assembly such as described wherein thetpiston d a d pi n hea e epara e uni s, onstructed and joined in a particular manner to assure the proper alignment and action'thereof as; well as to jointly accommodatea discharge check valve assembly which latter is ofisi mple form by reason ofthe construction and arrangement of the rod and piston head. v

Yet another obje t is to p de a valved pis on assembly in which a single pin holds the piston r and p ton, as W l as he check valve ass m ly therein, p op rly assemb ed r lation s ject to ready disassembly and replacement, of parts of the entire unit. I With the foregoing objects in view, together w h ch ot r bj ts and advanta es as'may subsequently appear, the invention resides in the parts and in the combination, construction and arrangement of parts hereinaftergdescribedand claimed, and illustrated by Way of example in the accompanying drawing, in which: v

Fig. 1 is a fragmentary side elevation of a pump in which the present invention is embodied;

Fig. 2 is a fragmentary longitudinal sectional view of the pump'showingthe action of the valved piston during one stroke thereof;

i 3 s a iew s milarto Fig. showinelthe stroke; .s, r t Fig. 4 is a cross-sectional view taken onthe line 4v4ofFig.2. ,r As s o n in th a mpa yin d awin ,mv

mp ov d va ed pi on is embodied n a, pump action of thevalvedpistonduring'thri opposite port 1 controlled by intake check valve .8 and I a dischargeport 9.

A suitable stuffing box in closes the'end of the cylinder opposite the end closed by'the BOIlStILlGn tion of the cylinder for accommodating the check valve 8,

Slidable throughthe-stuffing box In into the 7 cylinder 6, is a pistonrod l'l which issubject to reciprocation asby'means of; a lever 12 fulcrumedat i3 onfa bracke't l4 carried by the cylinderjtherej. being ailink l5; connecting the leverwith'saidfrodl I In accordance with my invention apistonf'on f pistonf ead "Seas a separate part is secured vto the piston rod il by means of a pin ll passed through aligned openings l8 and [9 in the piston and rodrespectively, therebeing the usual sealing ring groove 20in the piston and sealing ring 21 in said groove to prevent leakage betweent the cylinder wall and piston.

As here shown the piston has the reduction forming interiorly of the bore a valve seat 24 for a ball check valve 25 freely the end of said rod. Opening into this counterbore arev opposed. radial discharge ports 28 which are adapted to register with corresponding ,op--

posed radial ports in the socketed end of the piston rod H, the ports 28 and 29 being spaced approximately from the pin-receiving openings l8 and 19in the piston and rod respectively.

'As here shown the ports 29 are spaced somewhat inwardly of the squared end of therod and the portslg are correspondingly spaced from' the planeof shoulder 21, thus providing imperforate socketed portions of the rod and piston at the shoulder 21 to; assure stability and ment of the piston and rod.

Formed inthe socketed'end of the piston rod 5 sons to register with the bore 22 in the piston head, as a continuation oi said bore, is anaxial" bore 3t afi'ording communication ofgthe bore 22 With the registering ports 2a and 129;.

sirably in such a manner as to'reduce itsdiameter to provide an annular space between it' and the H V cylinder gwhereby. fluidmay tflowffreely through which includes a cylinder 5 havin iorl intake 5 the ports 28,ithus:completingasbyepass passage:-

' an tan borezz one end of which is reduced and opens through the outer end of the piston as an intake port,

proper alignthis connection 'itis seen. that'the inner 1 or. i'slnrt jend portion 3| of the piston throughwhich portiona 'thefpQrt-s zfl extendiis. exteriorly'gcut away, de-

way which includes the port 23, bores 22 and '30 and ports 28 and 29. This passageway is comparatively large and direct andafiords a large volume flow per stroke of the piston. u

The ball check valve 25 is urged against'its hereof is assembled as shown inFig;-2. In straddling the pin I? the U-shaped member 33 is held" V j of said b'ore,ra piston rod having an end port on against displacement as .an efiective seat and as;

sembly linkfor the spring and valve unit, as a .v

whole. By this arrangement the. :pin'. l'lf holds the piston rod and the valve unit in assembled relation.

The inner'end of the bore which the legs of the Ueshaped member will seat when initially engaged in the bore 38 in assembling'the unit. When the openings I8 and [9 are in registration and the pin I! is inserted therein,

7 the ends of the pin are sufiiciently tapered to cause the pin to slide past the bight 'portion of the LJ-shaped member between the legs thereof so that the member will seat on the pin asshowjn in Fig. 2 with the'legs slightly spaced fromcontact with the conical depression 34. Thi s arrangement makes for an easy assembly ofthe unit and assures the holding of the member 33, spring 32 and ball valve'in. properly assembled flowthrough the by-pass passageway'when the t 7 ball valve is unseated. The socketing of the rod in the piston as here provided and the manner 'in which the valve is mounted in the registering bores of the rod and piston make for a small,

compact assembly subject to easy assembling and disassembling. U I 'On the forward stroke of the piston assembly 1 the check valve 25 is unseated by fluid pressure while the intake check valve 8 is forced against its seat' and fluid will pass freely through port I 23, bores 22v and 39 and registering ports 28 and 29 thus by-passin'g thepiston and passing out through th discharge port 9. v 1

Onthe opposite or intake stroke of the piston the pressure of the fluid between the discharge port 9 and discharge valve 25' closes the latter while the suction action opens intake valve 8 thus allowing fi lid tobe drawn into the cylinder 6. I K i It will be apparent that I have provided a novel valved piston assembly which will attain the obf ject, hereof in a particularly efiicacious manner by'reason of the construction relative arrangement and cooperation of the separate piston rod and piston head elements and the manner in whichthe discharge valve is combined therewith. V While I have shown and described a specific embodiment of my invention, I do not limit myself to' the exactdeta'ils of construction set forth,

' Fand'the invention embracessuch changes, inodificationsand equivalents of the parts and their formation and arrangementasj come within'the steag r ci is formed with a conical depression e l against extending axially therethrough, said bor being reduced at one end to define a valve seat interiorly of the bore, the other end of said bore being enlarged to define a piston-rod receivingsocket and a stop shoulder, one end portion of said head being of smaller diameter than the remaindergof said head; and adapted to; define a U space between said end portion and the cylinder in which the head is operated, a discharge port extending from the exterior of said reduced end portion and opening into said enlarged portion,

mounted in said socket and abutting said shoulder, said end portion of said rod having an axial boreregiste'ring with'the bore in said head and being formed "with a discharge port aiTording 'communication 'of said registering bores with 2. In a structure of the character described; 7

a piston cylinder, a piston head having a bore extending axially therethrough, said bore being reduced at one end to define a valve seatiinteriorly of the bore, the other end of said bore "being enlarged to define a piston rod receiving- V a piston cylinder, a' piston headhaving'a bore socket 'and a stop'shoulder, one end portion'of said head being of smaller diameter than the re- 'mainder of said head'and adapted to define a 7 space between sa'id endportion and the cylinderin which the headis operated,"a discharge port extending from the exterior of said reduced end portion and opening intosaidbnlarged portion of said bore, a piston rod having an end portion mounted in said socket and abutting said shouldensaid end portion of said rod'having an axial boreregistering' with the bor in said head and being formed with a discharge port affording or communication of said registering bores with the discharge port in said head, a spring loaded check'valve assembly mounted on said bores and normally seating on said valve seat, a fastening pin inserted through said head and rod for holding them together, said check valve assembly includinga valve member, a spring abutting said valve at one, end, and a U-shaped spring'seat abutting the other end'of' said spring and straddling said pin within the bore in said rod.

3. In a structure of the character described, a piston cylinder, a piston head having a bore extending axially therethrough said bore "being reduced at, one end to define a valve seat interiorly of the bore, the other end of said bore being enlarged to define a piston-rod receivingsocket and a stop shoulder, one end portion of said head being of smaller diameter than the remainder of. said'head and-adapted to define a space between said end portion and the cylinder in which the head-is operated',ta-:discharge port extending from the exterior of said reduced end portion and opening into saidenlarged portion of said bore, a piston rod having an end-portion mounted in said socket and abutting said shoulder, said end portion of'said rod having an axial bore registering with the bore insaid headfsaid than the bore in said head adapted to seat on said-valve seat, a springurging said'discharge valve against its seatand extending into the bore insaid rod, a spring keeper'member mounted in the bore in said rod, and a fastening pin extending through said head and rod disposed to hold the spring keeper member in place as well as to secure the piston rod and piston head together.

4. In a structure of the character described, a piston cylinder, a piston head having a bore extending axially therethrough, said bore being reduced at one end to define a valve seat interiorly of the bore, the other end of said bore being enlarged to define a piston-rod receivingsocket and a stop shoulder, one end portion of said head being of smaller diameter than the remainder of said head and adapted to define a space between said end portion and the cylinder in which the head is operated, a discharge port extending from the exterior of said reduced end portion and opening into said enlarged portion of said bore, a piston rod having an end portion mounted in said socket and abutting said shoulder, said end portion of said rod having an axial bore registering with the bore in said head, said end portion of said rod having a radial discharge port registering with the discharge port in said piston head and opening into the bore in said rod, a discharge check valve of smaller diameter than the bore in said head adapted to seat on said valve seat, a spring urging said discharge valve against its seat and extending into the bore in said rod, a spring keeper member mounted in the bore in said rod, and a fastening pin extending through said head and rod disposedto hold the spring keeper member in place as well as to secure the piston rod and piston head together, said keeper member being U-shaped and arranged to straddle said pin.

5. In a structure of the character described, a piston cylinder, a piston head having a bore extending axially therethrough, said bore being reduced at one end to define a valve seat interiorly of the bore, the other end of said bore being enlarged to define a piston-rod receivingsocket and a stop shoulder, one end portion of said head being of smaller diameter than the remainder of said head and adapted to define a space between said end portion and the cylinder in which the head is operated, a discharge port extending from the exterior of said reduced end portion and opening into said enlarged portion of said bore, a piston rod having an end portion mounted in said socket and abutting said shoulder, said end portion of said rod having an axial bore registering with the bore in said head, said end portion of said rod having a radial discharge port registering with the discharge port in said piston head and opening into the bore in said rod, a discharge check valve of smaller diameter than the bore in said head adapted to seat on said valve seat, a spring urging said discharge valve against its seat and extending into the bore in said rod, spring means in said bores for yieldingly holding the discharge valve seated, and a removable fastening element inserted through the reduced end portion of said piston head and said rod to hold the rod socketed in the head and said boresand said discharge ports in registration.

6. In a structure of the kind described, a piston cylinder, a piston head having a bore extending axially therethrough, said bore being reduced at one end to define a valve seat interiorly of the bore, the other end of said bore being enlarged to define a piston-rod receiving-socket and a stop shoulder, one end portion of said head being exteriorly cut away to define a space between said end portion and the cylinder in which the head is operated, said space extending to the inner end of said cut-away portion and opening into said enlarged portion of said bore, a piston rod having an end portion mounted in said socket and abutting said shoulder, said end portion of said rod having an axial boreregistering with the bore in said head and being formed with a discharge port affording communication of said registering bores with the discharge port in said head, a spring loaded check valve assembly mounted on said bores and normally seating on said valve seat, and a fastening pin inserted through said head and rod for holding them toether.

'7. In a valved piston assembly, a cylinder, a piston head reciprocable in said cylinder and having a bore extending axially therethrough, said bore being reduced at one end to define a valve seat interiorly of the bore, the other end of said bore being enlarged to define a piston-rod receiving-socket and a stop shoulder, one end portion of said head being exteriorly cut away to define a space between said end portion and the cylinder in which the head is operated, said space extending to the inner end of said piston head, a discharge port leading from the exterior of said cut-away portion and opening into said enlarged portion of said bore, a piston rod .having an end portion mounted in said socket and abutting said shoulder, said end portionof said rod having an axial bore registering with the bore in said head, said end portion of said rod having a radial discharge port registering with the discharge port in said piston head and opening into the bore in said rod, a discharge check valve of smaller diameter than the bore in said head adapted to seat on said valve seat, a spring urging said discharge valve against its seat and extending into the bore in said rod, a

spring keeper member mounted'in the bore in said rod, and a fastening pin extending through said head and rod disposed to hold the spring keeper member in place as well as to secure the piston rod and piston head together.

OTTMAR A. KEHLE. 

